{"note":"bim_versions 導入後の保存のみ記録 (それ以前は bim_canonical 上書きで履歴なし)","ok":true,"slug":"u-willowbrookbungalow-fny3jsjs","versions":[{"created_at":"2026-06-11T04:23:35Z","element_count":72,"note":"5軸GA polish 47->97 by M5 (autonomous)","saved_by":"mcp","sha256":"9bccdd4dcee80ecf5dcde653206f1c1115c54d1dbb530ad33fa2b6400e650352","version":3},{"created_at":"2026-06-11T04:09:09Z","element_count":117,"note":"loop3: 設計時延床 85.0㎡ を投入 (見積過大の根治)","saved_by":"mcp","sha256":"292f33ac1a67c4f1957b58d221e09fd178896b9c5424d06b3f3954afdde071a1","version":2}]}